The Way the Ball Bounces

The gymnasium and the library represent the extremes of academic balance in an educational institution. The library represents intellectual education. The gymnasium is the center of physical education. The size and complexity of each is related directly to the age, size, diversity and population of a school's students.

Given the emotional attachment between people and sports, it is remarkable how little attention has been devoted to specifying and regulating the interior environment in which these activities occur. It is only recently that physicians and physical-education specialists have begun to understand the effect of the physical environment on the human body. Still, the rules of team sports are liberal about the nature of the gymnasium environment.

Rules of the game

In volleyball, for example, the rules of the game do not take great care to define the floor. As long as the floor surface is flat, horizontal and uniform, it is within the rules. The fact that volleyball can be played on a beach demonstrates the insignificance of the floor surface.

In basketball, however, NCAA rules are specific about how high a ball bounces, so the type of floor used is critical to meeting those guidelines. The rules state that the air pressure in a ball shall be such that when the basketball is dropped vertically from a height of six feet, it will rebound to a certain height. For instance, in women's basketball the rebound must be not less than 51 inches (when it strikes the least resilient part of the floor) and not more than 56 inches (for the most resilient part of the gym floor). When designing a gymnasium, school officials must make sure they choose floor materials with the right amount of resilience.

Living up to standards

About 20 years ago, the international sports community formulated a set of standards called the DIN Standards, by which the resilience of a sports floor could be measured. The Otto-Graf Institute, an affiliate of Stuttgart University in Stuttgart, Germany, developed the standards. When a floor is tested and passes the DIN standard tests, it is “DIN Certified.” The “Ball Rebound” DIN requirement for a sports floor is 90 percent. The ball rebound compares the wood floor rebound to the ball rebound of a concrete floor from the same height. School officials can determine the resilience of a floor material by visiting a manufacturer's research facility for demonstrations.

It is not the ball which is most affected by the resilience of the floor — it is the athlete's feet and body. The more resilient the floor, the quicker the athlete will tire — imagine running on snow or sand. The less resilient the floor, the more damaging a fall can be. If the floor does not absorb some of the impact of the footfall, the human leg bones and joints will have to do the job.

Once school planners take into account the resilience of a gym floor, they should consider the size or age of the people who will use the floor. If the resilience standard is ideal for a certain weight of person, someone above the weight will find it less resilient; a person below the weight will find it more resilient. Ideally, a gymnasium floor for elementary school children would be different from one used exclusively by adults. The gymnasium remains a large box of space, but how it is used evolves with the age of its users.

Floor function

The floor surface of a gym floor for an elementary school is designed primarily for exercise, recreation and simple team sports. It often is used for a variety of additional purposes — some of them may not have any sports connection at all. The gym can be used as a cafeteria, auditorium or both. The community may use it for town meetings. Street shoes are commonly used on such floors.

If the gym accommodates many functions, schools should consider alternatives to wood for the floor surface. Artificial gymnasium surfaces have the same resilience, but a different wear characteristic than wood floors. Water, sand and salt tracked in by street shoes are a bad combination for any wood floor.

As students reach middle school age, athletics and league sports teams become more prevalent, and the locker rooms and possible fold-up seating in the gym become an important facility issue. The gym floor for these students is more likely to be a higher-maintenance, traditional wood floor.

As a campus grows, a school may need to build a new gym or change the original use of an athletic facility. In some grade 7-12 schools, the volume and proportions of a former gym may make it suitable for conversion into either an auditorium or even a library.

In a larger school, the gym often will be a standalone “fieldhouse” with ample space for multiple team locker rooms. When locker rooms become a significant part of the building, other teams that do not use the gym may play a role in the locker design. For example, the swim team might share locker room space with the football team.

In these facilities, teams from schools become frequent visitors and they can raise security concerns. Dividing curtains or sliding walls are installed to permit simultaneous usage. Other schools or community groups may want to use the building on weekends — reinforcing the need for separate security and HVAC systems. In a high school, athletic officials may want an indoor track. Schools must make sure that the materials used for the running track have the proper resilience.

At the college level, a fieldhouse may contain a large gymnasium, squash courts and an indoor track. It may need to accommodate physical-education classes and intercollegiate sports, as well as intramural programs. Students living on campus become dependent on these facilities for exercise and for social purposes.

Once the physical-education needs of an educational institution expand to the point of needing separate facilities, a new problem may emerge: how to light the facility efficiently. An athletic building typically is tall, and the walls often are windowless. Despite the lack of windows, daylight can be used to illuminate a fieldhouse, especially when cupped rooftop monitors are used to reduce the glare.

The use of windows in the walls of a gymnasium can distract athletes and create a breakage liability. On the other hand, the blank exterior walls of a gym may be viewed as an eyesore. Sometimes the problem is so extreme that the gymnasium building is sunken into the ground. In other situations, the athletics buildings are built adjacent to athletic fields and at the perimeter of the campus.

Rush, AIA, CSI, is an architect with The Office of Michael Rosenfeld, Inc., Architects.